Service Manual
46
Installation and Maintenance
3. Compressor low pressure protection (E3)
Start
Is the terminal of low
pressure switch is properly connected?
no
Reconnect it firmly to make
sure it is properly contacted
no
no
no
no
no
yes
yes
yes
yes
yes
yes
yes
Malfunction is
eliminated
Malfunction is
eliminated
Malfunction is
eliminated
End
Is the system pressure higher
than the operation pressure value of
low pressure switch?
Charge refrigerant according
to the system requirement
Replace the low
pressure switch
In power-off status, check if
the two terminals led out from the switch are
put through?
The mainboard is abnormal;
replace the mainboard
